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ANATOMY OF 



It consists of four masses : one many times larger in the adult 

 than the second, and called cerebrum ; a second, called cerebellum, 



pronounced it fibrous ; and Bonnet, Herder, and many others, conceived a fibrous 

 structure so fit for the operations of the mind that they adopted this opinion. But 

 Soemmering and Cuvier did not venture to consider it fibrous throughout; and 

 many moderns, the brothers Wenzel, for instance, declared that, after re- 

 peated experiments and most careful observation, the brain was not at all fibrous, 

 but equally pulpy throughout. Walter, Ackerman, and Bichat equally deny 

 the fibrous structure of the brain, and speak of the white part as only medullary. 

 (Gall, 1. c. vol. i. p. 235.) 



Professor Ehrenberg has lately found the proper substance of the brain and 

 nerves to be fibrous, under a microscope with a power of magnifying to 300 or 

 even to 800 diameters. In the white part of the the brain, he says, the fibres are 

 straight and cylindrical, with others like strings of pearls : in the medullary, 

 these knotted fibres only exist, contained in a dense network of blood-vessels, 

 and interspersed with plates and granules. He declares the large cylindrical 

 fibres to be tubular, and believes that the knotted are tubular also. All micro- 

 scopical observations require careful repetition by many individuals. (Poggen- 

 dorf 's Annalen der Physik und Chimie, No. 7. 1833.) 



